OpenXava is an AJAX Java Framework for Rapid Development ofEnterprise Applications.
In OpenXava you only have to write the domain classes in plain Java to get an AJAX application ready for production.
Open Source (LGPL).More than 180,000 downloads. 50 contributors. Active community. High productivity.Short learning curve. AJAX User Interface. Exhaustive documentation in English, French, Russian, Chinese and Spanish. Based in Java standards.